Marion County, Illinois
Marion County | |
|---|---|
Location within the U.S. state of Illinois | |
Illinois's location within the U.S. | |
| Coordinates: 38°39′N 88°55′W / 38.65°N 88.92°W | |
| Country | United States |
| State | Illinois |
| Founded | 1823 |
| Named after | Francis Marion |
| Seat | Salem |
| Largest city | Centralia |
| Area | |
• Total | 576 sq mi (1,490 km2) |
| • Land | 572 sq mi (1,480 km2) |
| • Water | 3.7 sq mi (10 km2) 0.6% |
| Population (2020) | |
• Total | 37,729 |
• Estimate (2023) | 36,673 |
| • Density | 66/sq mi (25/km2) |
| Time zone | UTC−6 (Central) |
| • Summer (DST) | UTC−5 (CDT) |
| Congressional district | 15th |
Marion County is a county located in the U.S. state of Illinois. According to the 2020 census, it had a population of 37,729. Its county seat is Salem. Marion County comprises the Centralia, IL Micropolitan Statistical Area, which is included in the St. Louis-St. Charles-Farmington, MO-IL Combined Statistical Area.